Diagnosis Of Invasive Fungal Disease Research Articles

Severe Scedosporium apiospermum Infection in a Recent Renal Transplant Recipient: Case Report

Infections in transplanted patients are still an important cause of morbidity and mortality. Among them, fungal infections with pathogens have become increasingly more prevalent in the last decade. We report the clinical course and management of disseminated Scedosporium apiospermum infection in a kidney transplant recipient, with microbiological isolation of the fungus in cerebrospinal fluid culture. S apiospermum is a fungus that is distributed worldwide and can be grown from soil samples or stagnant water. Disseminated infection is the most frequent form of infection, with cerebral involvement in most cases, which leads to a very high mortality (around 75%). Post-transplant renal infections require a thorough evaluation. Specifically, a high suspicion index is necessary, considering Scedosporium infection among the differential diagnosis of invasive fungal diseases in renal transplantation patients. It is essential to confirm the microbiological diagnosis for an adequate diagnosis and treatment.

Speciation of fungi using real time PCR with molecular beacons: Can we solve the enigma of diagnosis of invasive fungal disease?

BackgroundInvasive fungal diseases (IFDs) are difficult to diagnose and associated with high mortality rates, especially in the immunosuppressed. Species of Aspergillus and Candida are the cause of majority of invasive fungal disease however IFDs are also caused by Fusarium, Zygomycetes, Trichosporon, etc. Early detection is crucial for appropriate antifungal therapy. Blood cultures usually fail to isolate filamentous fungi, while detection of circulating beta-d-glucan or galactomannan antigens show variable sensitivity and specificity. There is a need of reliable, sensitive and specific diagnostic tests for IFDs. MethodsA real-time Polymerase Chain Reaction (PCR) assay with a universal primer/molecular beacon system was developed for detecting and speciating most of the pathogenic fungi implicated in IFD. A single-reaction assay was designed targeting a carefully selected region of the ITS2 and ITS5 subunits of the fungal rDNA gene along with four molecular beacons capable of differential hybridization to the amplicons of different species. This generated a signature set of melting temperatures using the standard strains. The assay was tested on clinical specimens from patients with suspected invasive fungal disease. ResultsThe assay was tested on 72 clinical samples and 72 healthy controls. Of these, 22 clinical samples (6/8 proven; 13/29 probable; 3/35 possible IFD, classified by the EORTC/MSG criteria) were positive by PCR and generated a set of melting temperatures enabling identification of the causative fungus. The assay was negative in all healthy controls. ConclusionThe molecular beacon assay is a promising tool providing a rapid method for detection and monitoring of invasive fungal disease in immunosuppressed patients.

Disseminated fusariosis in a pediatric patient with acute lymphoblastic leukemia and prolonged fever - a case report

Introduction. Infections caused by fungi of Fusarium species occur in immunocompromised individuals as disseminated diseases. Case Report. This case report presents a 5-year-old boy with acute lymphoblastic leukemia who developed a disseminated fusarium infection during reinduction chemotherapy. Fever was the main symptom and it lasted for 15 weeks. Refractory fever despite broad-spectrum antibiotics, as well as nausea, myalgia, pulmonary symptoms with detection of pulmonary infiltrates, liver and spleen involvement indicated an invasive fungal infection. The patient received fluconazole, voriconazole, liposomal amphotericin B and caspofungin. Since high temperature was persistent, diagnostic laparoscopy of the abdomen was done. Scattered lesions, up to 2 mm in diameter, were observed macroscopically on the surface of the liver and spleen. The liver culture was positive for Acinetobacter and Fusarium species. After 38 days of therapy with liposomal amphotericin B and 3 days of ciprofloxacin, the patient became afebrile. Itraconazole (according to the antimycogram) was continued during maintenance therapy. Abdominal ultrasound was completely normal after 5 months of treatment with itraconazole. This boy was our first patient with a disseminated fusarium infection. At that time, Fusarium was detected in the hospital water system and in hospital air samples. Conclusion. A timely diagnosis of invasive fungal diseases in children is a big challenge. Over the past decade, there has been an increase in survival rate of patients with invasive fusariosis due to much more common use of voriconazole or combined antifungal therapy.

Empirical antifungal treatment for diagnosed and undiagnosed invasive fungal disease in patients with hematologic malignancies

Background: Empirical antifungal therapy is effective in some patients with risk factors for invasive fungal disease (IFD) who do not qualify for the EORTC/MSG criteria for IFD, but who fail to respond to anti-bacterial and anti-viral therapy. Objective: This retrospective single-center study investigated the epidemiology of IFD and empirical antifungal therapy in patients with hematological malignancies. Methods: This study recruited 893 patients with hematologic malignancies who had failed to respond to anti-bacterial and anti-viral treatment and received antifungal therapy, but not for antifungal prophylaxis. Antifungal therapy regimens included amphotericin B, voriconazole, itraconazole and caspofungin. A total of 689 patients were diagnosed with proven, probable, or possible IFD, while 159 patients did not meet the EORTC/MSG criteria for IFD diagnosis but recovered with antifungal treatment, and 45 were excluded from having IFD. Effective treatment was defined as the disappearance or resolution of clinical symptoms of IFD. Results: Patients diagnosed with IFD underwent chemotherapy at a higher proportion, and had significantly higher neutrophil counts compared to those who did not qualify for the EORTC/MSG criteria for IFD but responded to antifungals. The mortality due to all causes within 3 months was significantly higher for patients diagnosed with proven IFD, compared with those who did not qualify for the EORTC/MSG criteria for IFD. There was no discontinuation reported due to adverse events of caspofungin. Conclusion: Empirical antifungal treatment could help save the lives of some patients with severe infections who are strongly suspected of having IFD.

Clinical use of fungal PCR from deep tissue samples in the diagnosis of invasive fungal diseases: a retrospective observational study

ObjectivesTo assess the clinical use of panfungal PCR for diagnosis of invasive fungal diseases (IFDs). We focused on the deep tissue samples. MethodsWe first described the design of panfungal PCR, which is in clinical use at Helsinki University Hospital. Next we retrospectively evaluated the results of 307 fungal PCR tests performed from 2013 to 2015. Samples were taken from normally sterile tissues and fluids. The patient population was nonselected. We classified the likelihood of IFD according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG), comparing the fungal PCR results to the likelihood of IFD along with culture and microscopy results. ResultsThere were 48 positive (16%) and 259 negative (84%) PCR results. The sensitivity and specificity of PCR for diagnosing IFDs were 60.5% and 91.7%, respectively, while the negative predictive value and positive predictive value were 93.4% and 54.2%, respectively. The concordance between the PCR and the culture results was 86% and 87% between PCR and microscopy, respectively. Of the 48 patients with positive PCR results, 23 had a proven or probable IFD. ConclusionsFungal PCR can be useful for diagnosing IFDs in deep tissue samples. It is beneficial to combine fungal PCR with culture and microscopy.

Evaluation of the diagnostic performance of panfungal polymerase chain reaction assay in invasive fungal diseases.

Timely diagnosis of invasive fungal diseases (IFDs) is important, as delays in treatment initiation are associated with increased mortality rates. However, early diagnosis of IFDs in immunocompromised patients remains difficult. The conventional diagnostic methods currently used for IFDs are not sufficiently effective. Molecular tests, such as polymerase chain reaction (PCR)-based assays, have great potential to improve the early diagnosis of IFDs due to their sensitivity and specificity. In the present study, the diagnostic performance of panfungal PCR assays in IFD patients who received bone marrow transplantation was evaluated. The results suggested that panfungal PCR assay offered a quick and convenient guide for clinical decision-making by identifying higher numbers of fungal species in comparison with the conventional blood culture method. Furthermore, panfungal PCR assay exhibited a sensitivity of 93% and a specificity of 71% in the diagnosis of IFD patients based on the EORTC/MSG criteria. Thus, the present study concluded that the reported PCR-based method was effective and sensitive in early IFD diagnosis and should be integrated into clinical decision-making for the treatment of IFDs in the future.

International Collaborative on Contemporary Epidemiology and Diagnosis of Invasive Fungal Disease in Children.

International Collaborative on Contemporary Epidemiology and Diagnosis of Invasive Fungal Disease in Children.

Role of Molecular Biomarkers in the Diagnosis of Invasive Fungal Diseases in Children.

Invasive fungal diseases are important clinical problems that are often complicated by severe illness and therefore the inability to use invasive measures to definitively diagnose the disease. Tests for a range of fungal biomarkers that do not require an invasive sample-collection procedure have been incorporated into adult clinical practice, but pediatric data and pediatric-specific recommendations for some of these diagnostic tools are lacking. In this review, we summarize the published literature and contemporary strategies for using the biomarkers galactomannan, (1→3)-β-d-glucan, Candida mannan antigen and anti-mannan antibody, and fungal polymerase chain reaction for diagnosing invasive fungal disease in children. Data on biomarker use in neonates and children with cancer, history of hematopoietic stem cell transplant, or primary immunodeficiency are included. Fungal biomarker tests performed on blood, other body fluids, or tissue specimens represent promising adjuncts to the diagnostic armamentarium in populations with a high prevalence of invasive fungal disease, but substantial gaps exist in the correct use and interpretation of these diagnostic tools in pediatric patients.

Diagnostic Imaging and Invasive Fungal Diseases in Children.

Invasive fungal disease (IFD) is a life-threatening condition, especially in immunocompromised children. The role of diagnostic imaging in children at risk for an IFD is multifactorial, including initially detecting it, evaluating for dissemination of infection beyond the primary site of disease, monitoring the response to antifungal therapy, and assessing for potential relapse. The objective of this review was to synthesize the published literature relevant to the use of various imaging modalities for the diagnosis and management of IFD in children.

Performance of Targeted Fungal Sequencing for Culture-Independent Diagnosis of Invasive Fungal Disease.

Identification of fungi causing invasive fungal disease (IFD) is critical for guiding antifungal therapy. We describe the performance and clinical impact of a targeted panfungal polymerase chain reaction (PCR) amplicon sequencing assay for culture-independent diagnosis of IFD. Between January 2009 and September 2016, 233 specimens, consisting of fresh and formalin-fixed, paraffin-embedded (FFPE) tissues and sterile body fluids with known diagnosis of IFD based on reference method results (n = 117), and specimens with negative fungal culture, but with microscopic and ancillary findings indicative of IFD (n = 116), were included. PCR amplicons from the internal transcribed spacer 2 and the D2 region of 28S ribosomal RNA gene were sequenced and fungi identified. Sensitivity and specificity of fungal sequencing in specimens with known diagnosis were 96.6% (95% confidence interval [CI], 87.4%-99.4%; 58/60) and 98.2% (95% CI, 89.4%-99.9%; 56/57). In patients with suspected IFD, the diagnostic yield of fungal sequencing was 62.9% (73/116) overall and 71.3% (57/80) in patients classified with proven IFD based on the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and Mycoses Study Group (EORTC/MSG) criteria. Samples obtained by open biopsy had a significantly higher diagnostic yield (71.5% [40/56]) compared with core-needle biopsy (50% [17/34] P = .04) and fine needle aspiration (0% [0/2]; P = .009). Additionally, D2 sequencing diagnosed 5 cases of invasive protozoal infections due to Toxoplasma gondii (n = 3), Trypanosoma cruzi, and Leishmania species. Sequencing results altered patient management in the majority of suspected cases. The targeted fungal sequencing assay allowed accurate identification of fungi causing IFD and additionally provided partial-protozoal coverage. The diagnostic yield was dependent on the amount of tissue available for testing.

MALDI-TOF MS and Filamentous Fungal Identification: A Success Story?

Purpose of Review The diagnosis of invasive fungal disease remains challenging in the clinical laboratory. In this paper, the use of matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for the identification of filamentous fungi as well as its application for antifungal resistance testing and strain typing is evaluated.

A prospective study of fungal biomarkers to improve management of invasive fungal diseases in a mixed specialty critical care unit

PurposeThe diagnosis of invasive fungal diseases (IFD) in critical care patients (CrCP) is difficult. The study investigated the performance of a set of biomarkers for diagnosis of IFD in a mixed specialty critical care unit (CrCU). MethodsA prospective observational study in patients receiving critical care for ≥7days was performed. Serum samples were tested for the presence of: (1-3) - β-d-glucan (BDG), galactomannan (GM), and Aspergillus fumigatus DNA. GM antigen detection was also performed on bronchoalveolar lavage (BAL) samples. The patients were classified using published definitions for IFD and a diagnostic algorithm for invasive pulmonary aspergillosis. Performance parameters of the assays were determined. ResultsIn patients with proven and probable IFD, the sensitivity, specificity, PPV and NPV of a single positive BDG were 63%, 83%, 65% and 83% respectively. Specificity increased to 86% with 2 consecutive positive results. The mean BDG value of patients with proven and probable IFD was significantly higher compared to those with fungal colonization and no IFD (p value<0.0001). ConclusionNew diagnostic criteria which incorporate these biomarkers, in particular BDG, and host factors unique to critical care patients should enhance diagnosis of IFD and positively impact antifungal stewardship programs.

A Review of Diagnostic Methods for Invasive Fungal Diseases: Challenges and Perspectives

Invasive fungal diseases are associated with a high morbidity and mortality, particularly in the context of immunosuppression. Diagnosis of invasive fungal diseases is usually complicated by factors such as poor clinical suspicion and unspecific clinical findings. Access to modern diagnostic tools is frequently limited in developing countries. Here, we describe five real-life clinical cases from a Brazilian tertiary hospital, in order to illustrate how to best select diagnostic tests in patients with different fungal infections.

Invasive pulmonary aspergillosis in a child with acute myeloid leukaemia: pharmacotherapy and surgical management

This paper reports on diagnostic and therapeutic management of pulmonary invasive fungal disease (IFD) in a child with relapsed acute myeloid leukaemia, undergoing chemotherapy followed by hematopoietic stem cell transplantation. Surgical management with resection of the involved lung tissue was based on the location of fungal infiltrates close to large circulatory vessels. After examination of resected pulmonary tissue, a diagnosis of proven IFD was done. This case report is an example that aspergillosis is usually the cause for pulmonary IFD. Pharmacotherapy of pulmonary IFD should be based on compounds with good penetration to lung tissue: amphotericin B lipid form or voriconazole.

Clinical implications of serum galactomannan measurement in patients with acute invasive fungal rhinosinusitis.

Acute invasive fungal rhinosinusitis (AIFR) is an aggressive opportunistic infection with a high mortality rate. Recently, non-invasive techniques have been introduced for diagnosis of invasive fungal disease. The purpose of this study is to evaluate the diagnostic significance of serum galactomannan measurement in patients with AIFR. We conducted a retrospective case-control study of 28 patients with AIFR and 36 fungus ball (FB) patients. We evaluated clinical, laboratory, and pathologic findings along with disease course. In 28 patients with AIFR, there were 21 cases of invasive aspergillosis (IA) and 7 cases of invasive mucormycosis (IM). The control group was comprised of 36 patients with FB. The three-group analysis showed a statistically significant difference among the groups. At the cut-off value of 0.48, the sensitivity and specificity were 71.4% and 93.0%, respectively. Comparison of mean serum galactomannan levels in 5 non-survivors and 9 survivors at initial measurement showed no significant difference, but that became significantly different 1 week later. Statistical analysis showed that the levels of serum galactomannan decreased significantly according to the measurement-point in within survivor-group analysis. The difference in between survivor-groups analysis was also significant. Serum galactomannan measurement seems useful for early diagnosis and discrimination of fungal species in patients with AIFR. In addition, clinical outcomes may be related to the levels and patterns of serum galactomannan, especially in IA. The appropriate measurement of galactomannan might be helpful in treating the patients at high risk for AIFR.

Clinical implications of serum galactomannan measurement in patients with acute invasive fungal rhinosinusitis

Acute invasive fungal rhinosinusitis (AIFR) is an aggressive opportunistic infection with a high mortality rate. Recently, non-invasive techniques have been introduced for diagnosis of invasive fungal disease. The purpose of this study is to evaluate the diagnostic significance of serum galactomannan measurement in patients with AIFR. We conducted a retrospective case-control study of 28 patients with AIFR and 36 fungus ball (FB) patients. We evaluated clinical, laboratory, and pathologic findings along with disease course. In 28 patients with AIFR, there were 21 cases of invasive aspergillosis (IA) and 7 cases of invasive mucormycosis (IM). The control group was comprised of 36 patients with FB. The three-group analysis showed a statistically significant difference among the groups. At the cut-off value of 0.48, the sensitivity and specificity were 71.4% and 93.0%, respectively. Comparison of mean serum galactomannan levels in 5 non-survivors and 9 survivors at initial measurement showed no significant difference, but that became significantly different 1 week later. Statistical analysis showed that the levels of serum galactomannan decreased significantly according to the measurement-point in within survivor-group analysis. The difference in between survivor-groups analysis was also significant. Serum galactomannan measurement seems useful for early diagnosis and discrimination of fungal species in patients with AIFR. In addition, clinical outcomes may be related to the levels and patterns of serum galactomannan, especially in IA. The appropriate measurement of galactomannan might be helpful in treating the patients at high risk for AIFR.

Current Algorithms in Fungal Diagnosis in the Immunocompromised Host.

Invasive fungal diseases (IFDs) are a major cause of morbidity and mortality in immunocompromised patients such as patients with hematological malignancies or allogeneic hematopoietic stem cell transplant recipients. Whereas the definite diagnosis of IFD requires invasive diagnostic procedures, imaging and noninvasive diagnostic assays may help in decision making with regard to the institution and the choice of antifungal agents, the duration of therapy, surgical intervention, and monitoring of fungal manifestations.Unfortunately, signs and symptoms of IFD are often nonspecific in the immunocompromised patient. Therefore, in immunocompromised patients with suspected IFD, all samples collected need to be cultured for fungi, and, in the case of specimens obtained by invasive diagnostic procedures, also microscopically examined. For high sensitivity of the cultural and microscopic approaches, specific media and stains, respectively, are crucial. Non-culture based method such as the detection of galactomannan or ß-d-glucan and molecular tools such as polymerase chain reaction may help in the early diagnosis of IFD. Imaging studies may be indicative for IFD, but invasive diagnostics such as bronchoalveolar lavage and/or biopsy should be pursued in order to identify the causative pathogen. This chapter summarizes the current knowledge on diagnosing IFD and proposes practical help in the use of diagnostic tools.

Isolation of Nucleic Acids for Fungal Diagnosis.

PCR can aid in the diagnosis of invasive fungal disease (IFD). While the large number of "in-house" methodologies drives technological diversity, providing robustness, they make it difficult to identify optimal strategies, limiting standardization, and widespread acceptance. No matter how efficient, PCR utility will be limited by the quality of extracted nucleic acid. This chapter highlights benefits and limitations affecting the nucleic acid extraction process, before focusing on recent recommendations that through multicenter evaluation have provided optimal and standardized methodology.

Serological Approaches.

The diagnosis of invasive fungal diseases (IFD) based on clinical, radiological, and conventional microbiological findings is not reliable and is often delayed. Non-culture-based methods with higher sensitivity and specificity may reduce diagnostic time and result in decreased IFD morbidity and mortality. These methods are now increasingly used to manage patients at risk of IFD. Among available biomarkers, fungal antigens have been investigated as an aid to early diagnosis and are predominantly used as screening tests to prompt antifungal treatment mainly in patients with hematological malignancies. The revised version of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) consensus definitions includes some of these biological markers (galactomannan, 1,3-beta-D-glucan, cryptococcus antigen).

Laboratory examination of invasive fungal disease in children and its evaluation

Pediatric invasive fungal disease(IFD) often lacks characteristic clinical manifestations and imaging changes.It is a severe disease in ICU and is unlikely to be diagnosed early.The diagnosis of IFD is typically based on laboratory tests targeting at the population at risk.The laboratory tests for IFD generally include direct tests(smear microscopy, fungal culture, histopathologic examination, etc.), serologic tests(tests for 1, 3-β-D dextran and galactomannan, etc.), and certain progresses have been made in molecular biological tests in recent years.It is key to diagnosis of IFD to use laboratory tests rationally and accurately interpret the laboratory results. Key words: Invasive fungal disease; Laboratory examination,